﻿using System;
using System.Collections.Generic;
using System.Text;
using System.Reflection;
using System.Runtime.InteropServices;
using System.Diagnostics;

namespace Spider
{
    class Singleton
    {
        [DllImport("User32.dll")]
        private static extern bool ShowWindowAsync(IntPtr hWnd, int cmdShow);
        [DllImport("User32.dll")]
        private static extern bool SetForegroundWindow(IntPtr hWnd);
        private const int WS_SHOWNORMAL = 1;


        public static Process RunningInstance()
        {
            Process current = Process.GetCurrentProcess();
            Process[] processes = Process.GetProcessesByName(current.ProcessName);

            //Loop  through the running processes in with the same name
            foreach (Process process in processes)
            {
                //Ignore the current process
                if (process.Id != current.Id)
                {
                    //Make sure that the process is running from the exe   file.
                    if (Assembly.GetExecutingAssembly().Location.Replace("/", "\\") ==
                        current.MainModule.FileName)
                    {
                        return process;
                    }
                }
            }
            return null;
        }
        public static void HandleRunningInstance(Process instance)
        {
            ShowWindowAsync(instance.MainWindowHandle, 3);

            SetForegroundWindow(instance.MainWindowHandle);
        }
    }
}
